It is estimated that up to 8% of children less than 3 years of age and 2% of adults are affected by food allergies. While food-induced allergic reactions are the most common cause of outpatient anaphylaxis, the majority of severe reactions of this kind are caused by peanuts and tree nuts. Most plant food allergens can be found among pathogenesis-related proteins, seed storage albumins and globulins, and α-amylase and protease inhibitors.
Cashew nuts have been associated with contact or systemic dermatitis (to cardol and anacardic acid found in the cashew nut shell oil1), atopic dermatitis, and IgE-mediated systemic allergic reactions.2-4 Pistachios are another allergenic member of the Anacardiaceae family and show extensive in vitro cross-reactivity with cashews.5,6 Cashew nuts are widely used in snack foods and as an ingredient in a variety of processed foods such as bakery and confectionery products.
By sequencing of the N-termini and selected internal digests, we have found that the major allergenic proteins in cashew nut are legumin-like proteins and 2S albumins. We have also identified a polypeptide allergen in the 7S superfamily, which includes vicilin-like and sucrose binding proteins. Herein, we disclose the sequence of a CDNA encoding this allergenic polypeptide, designated Ana o 1, and describe the characterization of the expressed recombinant polypeptide. In addition, we identify several linear epitopes and compare these to the allergenic peanut vicilin, Ara h1.7 